HIGH CISA KEV

CVE-2023-27351

CVSS v3

7.5

HIGH

EPSS Score

47.9%

exploit probability

CISA KEV

Yes

known exploited

Exploitation

SSVC status

Description

This vulnerability allows remote attackers to bypass authentication on affected installations of PaperCut NG 22.0.5 (Build 63914). Authentication is not required to exploit this vulnerability. The specific flaw exists within the SecurityRequestFilter class. The issue results from improper implementation of the authentication algorithm. An attacker can leverage this vulnerability to bypass authentication on the system. Was ZDI-CAN-19226.

CISA Known Exploited Vulnerability

Date Added
4/20/2026
Patch Due Date
5/4/2026
Ransomware Use
Unknown

Technical details

Published
4/20/2023

Frequently asked questions

What is CVE-2023-27351?

This vulnerability allows remote attackers to bypass authentication on affected installations of PaperCut NG 22.0.5 (Build 63914). Authentication is not required to exploit this vulnerability. The specific flaw exists within the SecurityRequestFilter class. The issue results from improper implementation of the authentication algorithm. An attacker can leverage this vulnerability to bypass authentication on the system. Was ZDI-CAN-19226.

Is CVE-2023-27351 actively exploited?

Yes. CVE-2023-27351 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, meaning it has been confirmed as actively exploited in the wild. CISA requires federal agencies to patch by 5/4/2026.

What is the CVSS score for CVE-2023-27351?

CVE-2023-27351 has a CVSS v3 base score of 7.5 (HIGH severity).

Is CVE-2023-27351 affecting your environment?

Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.